The putt is perhaps the single most difficult yet important shot in golf. Before a player may even stroke the ball, the player must visually examine the contour of the putting surface and judge its effect on the path of a ball rolling toward the hole from the current position of the ball. Other characteristics of the putting surface or other factors can also have a significant effect on the path of a putt already stroked and rolling toward the hole. The direction in which the grass generally grows, the length of the grass on the putting surface, the type of grass on the putting surface, moisture on the putting surface, imperfections in the putting surface like footprints, spike marks or ball marks carelessly repaired, wind and a golf ball in which the center of mass and geometric center do not coincide are just some of the factors that affect the path of a rolling putt and, to some degree, for which the player must account. After examining the putting surface between the ball and the hole and accounting for other factors, the player must then execute a stroke that causes the ball to roll in a precise initial direction and with the precise speed required so that the ball's path intersects the hole and with speed slow enough for the ball to fall into the hole. Because of its complexity, nuance and potential for randomness, putting a ball into the hole is the most difficult and most precise task in golf. Yet, a putt is the single type of stroke that is most often required during a round of golf. To complicate matters further, the player's visual perception of the target is skewed which leads to errors in alignment because the player does not face the target while addressing the ball or stroking a putt. Instead, the player views the target while looking laterally down the intended target line. This sub-optimal visual perspective causes visual distortion that interferes with the player's ability to align the putting stroke with the target line that was chosen while standing behind the ball and looking toward the hole in order to determine the intended target line. This visual effect is detailed in a book entitled "See It & Sink It--Mastering Putting Through Peek Visual Performance" by Dr. Craig L. Farnsworth.
Golf courses are designed and standards for scoring are set based on the assumption that a player will be able to hit the ball onto the putting surface in two strokes less than par for each hole. Once on the ball is on the putting surface, the player is allowed two putts to stroke the ball into the hole in order to play the hole at par. Thus, an 18-hole golf course is designed to allow 36 putts in a round of golf played at par. Most, though not all, 18-hole golf courses play to a par of 72, which means that putting constitutes approximately 50% of the strokes prescribed for a round of golf.
The importance of putting in golf is illustrated by the professional careers of many notable players. Sam Snead, the winner of more officially sanctioned professional tour events than any other player, is a notable example of an extraordinary player who struggled with his putting stroke late in his career. In an attempt to cure his wavering putting stroke, Sam Snead adopted a croquet-style putting stroke in which he straddled the target line of his putt, drew his putter back between his legs and struck the ball with a pendulum-like swing along the target line. His croquet-style putting stroke worked relatively effectively for him until the Royal & Ancient Golf Association and the United States Golf Association (the "USGA") changed the Rules of Golf ("the Rules") to make his stroke illegal.
The Rules allow a player to use a modified croquet-style stoke in which the player stands with both feet on one side of the target line and faces the target. This type of stroke is thought by some, including the inventor, to be more effective for a number reasons. For example, the player may simultaneously address the putt and execute the stroke from a position that permits both eyes to focus on the target.
The Rules were also changed to make it more difficult to design a putter that would be useful for making such a stroke. The Rules allow the shaft of a putter to be connected to any point on the putter head and to have bent and straight portions, with the bent portion having a length measured along its axis less than or equal to 5 inches. The Rules also require that the projection of the straight portion of a putter shaft onto a plane perpendicular to the target line diverge at least 10.degree. from vertical. Additionally, the overall length of the shaft, measured along a straight-line extension of the straight portion of the shaft to the ground when the putter is grounded, must be greater than or equal to 18 inches.
When using a traditional putting stroke, a player faces a direction generally perpendicular to the target line and thus must turn to look down the target line when preparing to stroke the ball. This creates a visual distortion that interferes with the player's ability to perceive accurately the location of the target. Because of this effect, most right-handed players perceive that the target is farther right than its actual location. Additionally, the player loses depth perception in viewing the target in such a manner because the effective distance between the players eyes (in a direction perpendicular to a line from the eyes to the target) is small when viewing the target from such a traditional stance.
Aside from the disadvantages in viewing the target and determining the proper line and distance to the target stemming from the use of the traditional putting stance, this stance also interferes with the mechanics of putting. Specifically, the primary axis around which the putter swings during a traditional putting stroke is defined by the player's spine. When taking a traditional stance and swinging a putter from such a stance, the player swings the shoulders in such a manner that the putter rotates around the spine. Assuming a fixed relationship between the player's hands and spine, the resulting stroke follows an arc that moves inside the target line on the back swing, to the target line at impact (at least if performed properly), and back inside the target line after impact. When traveling along such an arc (and still assuming the fixed spatial relationship between the hands and the spine), the face of the putter also rotates relative to the target line during the stroke. On the back swing, the putter face opens to the target line, at impact the putter face is perpendicular to the target line (again if the stroke has been properly executed), and the putter face closes to the target line after impact.
A noted contemporary instructor on putting, Dave Pelz has studied the effects of misalignment relative to the target line (when the putter strikes the ball) of (1) the putter's swing path, (2) the putter face and (3) the optimum hitting location on the putter face on the ultimate putting success. Mr. Pelz has found that all three types of misalignment cause significant error in the putting stroke and thus decrease the chances of the ball going into the hole. However, he opines that misalignment of the putter face causes the largest deviation from the player's intended path of any particular putt. In order to reduce the possibility of misalignment of the putter face, path and hitting location, Mr. Pelz recommends that the player's putting stroke start with the optimum hitting location on the putter face immediately adjacent to the ball and that the stroke travel along a path aligned with the target line with the face remaining perpendicular to the target line for the entire stroke. However, as explained above, when a player swings the putter around the spine only, such a stroke does not result. In fact, the putter path corresponds to the target line at only one point in its arc and the face is perpendicular to the target line at only one point in its arc--and these two points do not necessarily coincide. Thus, to execute a stroke with a path along the target line and with a square putter face while using a traditional putting stance and stroke requires a complex combination of multi-axis rotational movements. Executing such a multi-axis stroke in a manner that accomplishes the primary and complex task of causing a ball to roll smoothly along a precise path at a precise speed renders the most difficult and important stroke in golf even more difficult. Some of the most common practice aids and drills in golf are designed purely to enable players to ingrain this complex, multi-axis putting stroke into their muscle memory. Other players simply concentrate on swinging the putter around only their spine and training themselves to hit the ball at the precise moment in time when the putter path, face and hitting location are correctly aligned with the target line. Thus, both widely adopted approaches to executing the traditional putting stroke suffer from disadvantages that interfere with the ultimate goal--putting the ball into the hole.
The only way in which to avoid the disadvantages associated with the traditional putting stroke is to swing the putter head around a horizontal axis of rotation that is perpendicular to the target line--exactly the result of Sam Snead's outlawed croquet-style stroke. It is possible, however, to design a putter within the Rules that allows the player to swing the putter on an arc defined by rotation around a horizontal axis that is perpendicular to the target line, or at least on an arc close to this optimum arc. The resulting putting stroke is executed while the player stands generally facing the target with both feet on one side of the target line. Numerous putters have been designed to allow a player to take such a stance and execute such a stroke, but always with some type of requirement to manipulate the club in a secondary manner not associated with purely swinging the putter around a horizontal axis perpendicular to the target line. Each of the following U.S. Patents describe a putter for use with modified croquet-style stance and stroke as described above, but they all have characteristics that interfere with the natural pendulum action of the putting stroke, or do not comply with the Rules.
______________________________________ U.S. Pat. No. Patentee(s) Issue Date ______________________________________ 3,574,349 Kropp 4/13/71 4,163,554 Bernhart 8/7/79 3,679,207 Florian 7/25/72 4,227,694 Drake 10/14/80 4,523,758 Guendling, Jr. 6/18/85 5,125,657 Beil 6/30/92 Re. 33,169 Leek 2/20/90 ______________________________________
Kropp, for example describes a putter suitable for use with a two-handed stroke in which the upper end of the grip lies vertically above the heel rather than the center of the face. Thus, if a player were to grasp Kropp's putter with one hand on the upper end of the grip, the natural tendency of the putter would be to hang such that a line from the upper end of the grip to the center of the face is angled toward the player when viewed from the front at address. Any attempt to use Kropp's putter in a one-handed putting stroke would likely result in the player striking the ball away from the center of the face. Bernhart and Florian describe putters that are similarly configured to Kropp's putter, but having a top end of the grip that is even more misaligned with the center of the face.
Guendling, Jr. describes a putter designed for use with a one-handed stroke in which the upper end of the grip does lie vertically above the center of the face when used in a stroke as is evident from Guendling Jr.'s FIG. 3. However, Guendling, Jr.'s putter does not comply with the Rules because the angle between the axis of the straight portion of the shaft of the putter in its normal address position and vertical is less than 10.degree. (it is actually 0.degree.). Leek, Drake and Beil describe putters that similarly do not comply with the Rules. Additionally, the Guendling, Jr. putter is shown to be of 10-26 inches in length, which violates the Rules requirement that the putter shaft be at least 18 inches long as measured from the top of the grip along the axis of the shaft or a straight-line extension of the shaft to the sole of the club.
Thus, a need continues to exist for a putter suitable for use with a modified croquet-style stroke that complies with the Rules and facilitates a natural, pendulum-type swinging stroke with little or no extraneous manipulation of the putter when making a stroke.